Sorry to say, it looks like you need a better system of cataloging if you really want them to come up nicely. The menu can handle it but the time it takes to load them on the first encounter is what's holding you up.
Even if you split it alphabeticaly would help.
I suppose if someone knows how to preload the data before the menu is opened, but then that will probably take longer for the initial page to load in some browsers. I don't remember anything like that, but you could search around.
I don't know backend so I'm no help there. Its usually quiet here around the weekends.
maz
